How do I add an existing directory tree to a project in Visual Studio?

You need to put your directory structure in your project directory. And then click "Show All Files" icon in the top of Solution Explorer toolbox. After that, the added directory will be shown up. You will then need to select this directory, right click, and choose "Include in Project."

https://i.stack.imgur.com/ub2DI.png

https://i.stack.imgur.com/oIDP1.png

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You can also drag and drop the folder from Windows Explorer onto your Visual Studio solution window.

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In Visual Studio 2015, this is how you do it.

If you want to automatically include all descendant files below a specific folder:

<Content Include="Path\To\Folder\**" />

This can be restricted to include only files within the path specified:

<Content Include="Path\To\Folder\*.*" />

Or even only files with a specified extension:

<Content Include="Path\To\Folder\*.jpg" >

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Copy & Paste.

To Add a folder, all the sub-directories, and files we can also Copy and Paste. For example we can:

Right click in Windows explorer on the folder, and Copy on the folder with many files and folders. Then in Visual Studio Solution explorer, right click on the destination folder and click paste. Optional add to TFS; Then in the top folder right click and check in to TFS to check in all sub-folders and files.

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You can use a symbolic link. This makes modifying the file in one project modify it in the other (as it's actually the same file).

To do this:

Open cmd prompt as administrator mklink /d [current project directory name] [directory in other project it should point to]

This has it's drawbacks and pitfalls, but I use it on occasion for duplicate libraries that need different names.

Edit for Anoop: Steps to add to Visual Studio:

Create link in the project folder using the steps above. In Visual Studio... select project in Solution Explorer. At the top of Solution Explorer... click the Show All Files button (may need to click it twice if already active). The link will now show in your project... right-click and choose Include In Project.

These are the steps I follow and works for a couple different projects.

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In Visual Studio 2017, you switch between Solution View and Folder View back and forth. I think this is a better option, because it will keep the solution cleaner. I use this to edit .gitignore, .md files, etc.

https://i.stack.imgur.com/P5tSD.png

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To expand on Yuchen's answer, you can include files and paths as a link. This is not the same thing as adding the existing items because it doesn't make an extra copy in your project's folder structure. It is useful if you want one canonical folder / file etc to be used in a lot of different places but you only want to maintain one version/copy of it.

Here is an example of what you can add to a *.csproj file to create the link

<Compile Include="$(Codez)\z.Libraries\Common\Strings\RegexExtensions.cs">
    <Link>Helpers\RegexExtensions.cs</Link>
</Compile>

<Compile Include="..\..\z.Libraries\MoreLINQ\MoreLinq\ExceptBy.cs">
    <Link>Helpers\ExceptBy.cs</Link>
</Compile>

<Content Include="C:\Codez\Libs\Folder\OtherFolder\**\*.*">
    <Link>%(RecursiveDir)%(Filename)%(Extension)</Link>
    <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
</Content>

$(Codez) is a Windows Environment variable I defined, you can use the built-in Environment variables in the same manner.

The last example group is a bunch of content files I need in the final output. See https://stackoverflow.com/a/11808911/492 and other answers & links there for more on that.

More MSBuild info at https://msdn.microsoft.com/en-us/library/bb629388.aspx

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I think I found a way to do this with the Compile Include=".\Code***.cs" What I wanted is to include code recursively under my Code folder.

Here is the project file sample.

<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="15.0" DefaultTargets="BuildTarget">
    <PropertyGroup>
        <OutputType>Library</OutputType>
    </PropertyGroup>
    <PropertyGroup>
        <StartupObject />
    </PropertyGroup>
    <PropertyGroup>
        <RootNamespace>Autogen</RootNamespace>
    </PropertyGroup>
    <ItemGroup>
        <Compile Remove="@(Compile)" />
        <Compile Include=".\Code\**\*.cs" />
    </ItemGroup>
    <Target Name="BuildTarget">
        <Message Text="Build selected" Importance="high"/>
    </Target>
</Project>

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In Visual Studio 2013, I couldn't get "Include in Project" to work when right-clicking on a folder. What did work is expanding the folder, selecting all the files then choosing "Include in Project". It was quite tedious as you have to do each folder one by one (but at least you can do all files in each folder in one go), and it appears to store the file path (you can see this by viewing properties on the file and looking at the "Relative Path" option.)

I am hoping to use this to deploy some data files in a Visual Studio Installer project, and it seems to pick up the included files and preserve their paths.

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Visual Studio 2017 and newer support a new lightweight .csproj format which has come to be known as "SDK format". One of several advantages of this format is that instead of containing a list of files and folders which are included, files are wildcard included by default. Therefore, with this new format, your files and folders - added in Explorer or on the command line - will get picked up automatically!

The SDK format .csproj file currently works with the following project types:

Class library projects

Console apps

ASP.NET Core web apps

.NET Core projects of any type

To use the new format, create a new .NET Core or .NET Standard project. Because the templates haven't been updated for the full .NET Framework even in Visual Studio 2019, to create a .NET class library choose the .NET Standard Library template, and then edit the project file to target the framework version of your choice (the new style project format can be edited inside Visual Studio - just right click the project in the Solution Explorer and select "Edit project file"). For example:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net46</TargetFramework>
  </PropertyGroup>
</Project>

Further reading:

Old csproj to new csproj: Visual Studio 2017 upgrade guide

Demystifying the SDK Project

MSDN: Additions to the csproj format for .NET Core

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I found no answer to my satisfaction, so I figured out myself.

Here is the answer to you if you want to add external source codes to your project and don't want to copy over the entire codes. I have many dependencies on other gits and they are updated hourly if not minutely. I can't do copy every hour to sync up. Here is what you need to do.

Assume this is structure:

/root/projA/src

/root/projA/includes

/root/projB/src

/root/projB/includes

/root/yourProj/src

/root/yourProj/includes

Start your VS solution. Right-click the project name right below the Solution. Then click the "Add", "New Filter", put the name "projA" for projA. Right-click on the "projA", click "Add", "New Filter", enter name "src" Right-click on the "projA", click "Add", "New Filter", enter name "includes" Right-click "projA"/"src", click "Add", "Existing Item", then browse to the /root/projA/src to add all source codes or one by one for the ones you want. Do same for "projA"/"includes" Do same for projB. Now the external/existing projects outside yours are present in your solution/project. The VS will compile them together. Here is an trick. Since the projA and projB are virtual folders under your project, the compiler may not find the projA/includes. If it doesn't find the projA/includes, then right click the project, select the "Properties". Navigate to "C/C++". Edit "Additional Include Directories", add your projA/include as such "../projA/includes", relative path.

One caveat, if there are duplicated include/header files, the "exclude from project" on the "Header file" doesn't really work. It's a bug in VS.

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As far as I can tell, the only way to do this in VS2010 is akin to the drag and drop method. Right click the solution to which you want to add a project. The application menu will have an add ... item. Opening that, you find that one of the options is to add an existing project to the solution.

In the dialog box that opens, navigate to the folder containing the project file for the solution and select it. VS will, as part of importing that project file, also import the entire directory and, I assume any subordinate directories which are part of that project.

As this does require an existing project file, it won't be impossible to import a directory tree until that tree has been converted to a project.

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